rs752848590

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001174150.2(ARL13B):​c.682G>A​(p.Glu228Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000000686 in 1,457,362 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E228Q) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

ARL13B
NM_001174150.2 missense

Scores

11
8

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.42

Publications

2 publications found
Variant links:
Genes affected
ARL13B (HGNC:25419): (ADP ribosylation factor like GTPase 13B) This gene encodes a member of the ADP-ribosylation factor-like family. The encoded protein is a small GTPase that contains both N-terminal and C-terminal guanine nucleotide-binding motifs. This protein is localized in the cilia and plays a role in cilia formation and in maintenance of cilia. Mutations in this gene are the cause of Joubert syndrome 8. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Mar 2010]
ARL13B Gene-Disease associations (from GenCC):
  • Joubert syndrome
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • Joubert syndrome 8
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ARL13BNM_001174150.2 linkc.682G>A p.Glu228Lys missense_variant Exon 5 of 10 ENST00000394222.8 NP_001167621.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ARL13BENST00000394222.8 linkc.682G>A p.Glu228Lys missense_variant Exon 5 of 10 1 NM_001174150.2 ENSP00000377769.3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.86e-7
AC:
1
AN:
1457362
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
724822
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33110
American (AMR)
AF:
0.00
AC:
0
AN:
44580
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39244
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85526
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53260
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
9.01e-7
AC:
1
AN:
1109596
Other (OTH)
AF:
0.00
AC:
0
AN:
60182
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Joubert syndrome 8 Uncertain:1
Jun 07, 2018
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with ARL13B-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamic acid with lysine at codon 228 of the ARL13B protein (p.Glu228Lys). The glutamic acid residue is highly conserved and there is a small physicochemical difference between glutamic acid and lysine. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Uncertain
0.031
T
BayesDel_noAF
Benign
-0.19
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.10
.;.;T;T
Eigen
Uncertain
0.54
Eigen_PC
Uncertain
0.59
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.89
D;D;.;D
M_CAP
Benign
0.029
D
MetaRNN
Uncertain
0.55
D;D;D;D
MetaSVM
Uncertain
-0.27
T
MutationAssessor
Benign
2.0
.;.;M;M
PhyloP100
5.4
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
-1.7
N;N;N;N
REVEL
Benign
0.086
Sift
Uncertain
0.0080
D;D;D;D
Sift4G
Uncertain
0.017
D;D;D;D
Polyphen
0.95, 0.40
.;P;B;B
Vest4
0.62
MutPred
0.26
.;.;Gain of MoRF binding (P = 0.0106);Gain of MoRF binding (P = 0.0106);
MVP
0.83
MPC
0.20
ClinPred
0.89
D
GERP RS
4.8
Varity_R
0.24
gMVP
0.48
Mutation Taster
=56/44
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs752848590; hg19: chr3-93755591; API